Recently, it has been made clear that the platelets and the arachidonic acid metabolites play an important role for the origin of thrombotic diseases such as cardiac infarction and the prevention therefrom, and the development of useful drugs therefor such as inhibitory agent of platelet aggregation is expected. On the other hand, with the diabetic neuropathy and complications of diabetes mellitus, the participation of aldose reductase has been made clear, thus the inhibition of the activity of aldose reductase will be connected with the therapy and the prevention of complications originating from diabetes mellitus.
Compounds having inhibitory effect on platelet aggregation or compounds having inhibitory effect on aldose reductase are widely searched separately. For example, the fact that quinazoline-1-alkanoic acid derivatives have the inhibitory effect on aldose reductase is disclosed in Japanese Unexamined Patent Publication No. Sho 62-96476, No. Hei 1-125322 and No. Hei 1-131164, but these compounds have no inhibitory effect on platelet aggregation. The quinazoline-3-alkanoic acid derivatives of the invention are novel compounds, and any prior art to allow to presume that the compounds of the invention have both the inhibitory effect on platelet aggregation and the inhibitory effect on aldose reductase cannot be found.
The purpose of the invention is to provide useful compounds as medicinal drugs having excellent inhibitory effect on aldose reductase together with strong inhibitory effect on platelet aggregation.